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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

A system for generation of near real-time feeds of user-customized hydrometeorology data-products from NEXRAD radar-data

Singh, Satpreet Harcharan 01 December 2010 (has links)
Hydrometeorology researchers use data-products like rainfall maps, quarter-hourly, hourly & daily rainfall accumulation maps, and reflectivity maps to drive their hydrological models. There are many sources available from which to generate such products e.g. (1) Weather-radar scan data, (2) Rain-gauge data and (3) Satellite maps, to name a few. Researchers, however, prefer to deal directly with the data-product, rather than deal with the details of sensor data-collection, data-management, storage, quality-control, processing and format conversion. Many researchers would additionally like a real-time continuous 'feed' of customized hydrometeorology data-products to drive their hydrological models in a real-time continuous fashion. Hydro-NEXRAD II is a new system that is currently being developed at IIHR-Hydroscience and Engineering (at The University of Iowa) to address this need. The system provides rapid and user-friendly access to the aforementioned user-customized hydrometeorology data-products in file formats convenient to researchers. Products are generated using near real-time Weather Surveillance Doppler Radar (WSR-88D) data from the National Weather Service's NEXRAD (NEXt generation RADar) radar-network. The architecture, design and engineering details of Hydro-NEXRAD II are the subject of this thesis.
252

Output limitations to single stage and cascaded 2-2.5μm light emitting diodes

Hudson, Andrew Ian 01 December 2014 (has links)
Since the advent of precise semiconductor engineering techniques in the 1960s, considerable effort has been devoted both in academia and private industry to the fabrication and testing of complex structures. In addition to other techniques, molecular beam epitaxy (MBE) has made it possible to create devices with single mono-layer accuracy. This facilitates the design of precise band structures and the selection of specific spectroscopic properties for light source materials. The applications of such engineered structures have made solid state devices common commercial quantities. These applications include solid state lasers, light emitting diodes and light sensors. Band gap engineering has been used to design emitters for many wavelength bands, including the short wavelength (SWIR) infrared region which ranges from 1.5 to 2.5 μm [1]. Practical devices include sensors operating in the 2-2.5 μm range. When designing such a device, necessary concerns include the required bias voltage, operating current, input impedance and especially for emitters, the wall-plug efficiency. Three types of engineered structures are considered in this thesis. These include GaInAsSb quaternary alloy bulk active regions, GaInAsSb multiple quantum well devices (MQW) and GaInAsSb cascaded light emitting diodes. The three structures are evaluated according to specific standards applied to emitters of infrared light. The spectral profiles are obtained with photo or electro-luminescence, for the purpose of locating the peak emission wavelength. The peak wavelength for these specimens is in the 2.2-2.5μm window. The emission efficiency is determined by employing three empirical techniques: current/voltage (IV), radiance/current (LI), and carrier lifetime measurements. The first verifies that the structure has the correct electrical properties, by measuring among other parameters the activation voltage. The second is used to determine the energy efficiency of the device, including the wall-plug and quantum efficiencies. The last provides estimates of the relative magnitude of the Shockley Read Hall, radiative and Auger coefficients. These constants illustrate the overall radiative efficiency of the material, by noting comparisons between radiative and non-radiative recombination rates.
253

Cultura de segurança do paciente e análise dos eventos adversos por meio do processo de enfermagem

Avancini, Karolline Bertoldo Angelim January 2019 (has links)
Orientador: Silvana Andrea Molina Lima / Resumo: O presente estudo teve como objetivo analisar os indicadores de segurança do paciente em unidade coronariana de instituição privada. Método: Estudo descritivo, transversal, com abordagem quantitativa, realizado a partir de dados e anotações do processo de enfermagem do Hospital dos Fornecedores de Cana localizado na cidade de Piracicaba-SP. Foram avaliados os indicadores de segurança do paciente, sendo descritos: Parte 1- Cultura de Segurança dos hospitais na perspectiva da equipe de enfermagem, sendo aplicado questionário sobre segurança em hospitais (HSOPSC), que possui 42 dimensões; Parte 2- Incidentes relacionados à assistência à saúde: os dados foram coletados a partir dos registros contidos no processo de enfermagem e relatórios gerenciais do serviço. Foram incluídos todos os registros dos pacientes, que foram hospitalizados na unidade por doenças coronarianas agudas ou crônicas, do período de 01 de janeiro a 31 de dezembro de 2017. Produto: Elaborar um vídeo explicativo sobre a segurança do paciente com enfoque nas metas internacionais e como realizar as notificações ao núcleo de segurança do paciente. Resultados: Houve um maior percentual de respostas positivas nas dimensões relacionadas ao trabalho em equipe (37,5%), aprendizagem da organização (56,25%), percepção da segurança do paciente (81,25%), respostas não punitivas ao erro (62,50%), feedback e comunicação sobre erros (37,5%), abertura para comunicação (50,0%), apoio a gestão hospitalar (62,5%), frequência de e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present study aimed to analyze the safety indicators of the patient in a coronary unit of a private institution. Method: Descriptive study, with a quantitative approach, based on data and annotations of the nursing process of the Hospital dos Fornecedores de Cana (Suppliers Hospital of Cana) located in the city of Piracicaba-SP.The safety indicators of the patient were evaluated, being described: Part 1- Safety Culture of the hospitals from the perspective of the nursing team, being applied a questionnaire on safety in hospitals (HSOPSC), which has 42 dimensions, Part 2 - Incidents related to health care: data were collected from the records contained in the nursing process and management reports of the service. We included all records of the patients, who were hospitalized in the unit for acute or chronic coronary diseases, from January 1 to December 31, 2017. Results: There was a greater percentage of positive responses in the dimensions related to teamwork (37.5%), organizational learning (56.25%), perception of patient safety (81.25%), non-punitive responses to error (62.50%), feedback and communication about errors (37.5%), openness to communication (50.0%), hospital management support (62.5%), ) and shift (43.8%). There was a higher percentage of negative responses in the staff-related dimension (43.75%). Of the incidents that occurred in the patients admitted to the UCO, 100% were identified as adverse events, with 52% loss of peripheral venous access (PVA), 27% of... (Complete abstract click electronic access below) / Mestre
254

The Resurgence of Islam in Turkey: A Search for Identity

Bali, Vandana 01 January 1994 (has links)
No description available.
255

Umman-manda and its Significance in the First Millennium BC

Adali, Selim Ferruh January 2009 (has links)
Doctor of Philosophy / Umman-manda (literally “Troops of Manda”) is an Akkadian compound expression used to denote military entities and/or foreign peoples in a diverse number of texts pertaining to separate periods of ancient Near Eastern history. The dissertation initially discusses the various difficulties in ascertaining the etymology of the second component of the term Umman-manda. A very plausible etymology is proposed based on new research on the semantic range of the Sumerian word mandum. The thesis then focuses mainly on the references made to the Umman-manda in the Neo-Assyrian and Neo-Babylonian sources, where it is used to denote the Cimmerians and Medes respectively. The starting point is that these references are making literary allusions to the Standard Babylonian version of the Cuthaean Legend. New information gained from these literary allusions provides insight into the significance of the term Umman-manda in the first millennium B.C.: it recalls the various attributes of the Umman-manda depicted in the Cuthaean Legend and applies these attributes to contemporary political events. The Cuthaean Legend envisions a powerful enemy that emerges unexpectedly from the distant mountains and establishes hegemony after a sudden burst of military power. This enemy will eventually be destroyed without the intervention of the Mesopotamian king. The thesis studies how the Neo-Assyrian and Neo-Babylonian sources allude to the Cuthaean Legend and in this way they identify the Cimmerians and the Medes as the Umman-manda.
256

Near-Field Scanning Optical Lithography for Nanostructuring Electroactive Polymers

Cotton, Daniel Vincent January 2007 (has links)
Research Doctorate - Doctor of Philosophy (PhD) / The photochemistry of poly{p-phenylene[1-(tetrahydrothiophen-1-io)ethylene chloride]} (PPTEC), a water soluble precursor of the semiconducting polymer, poly{p-phenylenevinylene} (PPV), has been studied both under atmospheric conditions and in environments devoid of oxygen. UV-visible spectroscopy and photoluminescence data has been used to provide a picture of the mechanistic pathways involved in UV irradiation of the PPTEC material. A new quantitative model for the effect of UV irradiation upon film morphology is presented. The technique of near-field scanning optical lithography (NSOL) has been used to produce arbitrary structures of the semi-conducting polymer poly{p-phenylenevinylene} at sizes comparable with optical wavelengths. Structures on this scale are of interest for integrated optical devices and organic solar cells. The structures are characterised using AFM and SEM and examined in the context of the electric field distribution at the NSOM tip. The Bethe-Bouwkamp model for electric field distribution at an aperture has been used, in combination with the developed model for precursor solubility dependence on UV energy dose, to predict the characteristics of lithographic features produced by NSOL. Fine structure in the lithographic features that are characteristic of the technique are investigated and their origins explained. Suggestions for the improvement of the technique are made. Presented here for the first time is a device manufactured by the technique of NSOL functioning as an optical device. The technique of NSOL is used to manufacture an optical transmission phase grating (or phase mask) of PPV, this was done as a proof of concept for device manufacture by this method and to demonstrate the potential usefulness of the unique characteristics of the technique. The phase mask was characterised using AFM and SEM and examined in the context of how well a diffraction pattern matches with theoretical calculations.
257

Contacts and trade at Late Bronze Age Hazor : aspects of intercultural relationships and identity in the Eastern Mediterranean

Josephson Hesse, Kristina January 2008 (has links)
<p>Hazor’s role in an international Late Bronze Age context has long been indicated but never thoroughly investigated. This role, I believe, was more crucial than previously stressed. My assumption is based on the very large size of this flourishing city which, according to documents, possessed ancient traditions of diplomatic connections and trade with Mesopotamia in the Middle Bronze Age. Its strategic position along the most important N-S and E-W main trade routes, which connected Egypt with Syria-Mesopotamia and the Mediterranean Sea with the city and beyond, promoted contacts. Hazor was a city-state in Canaan, a province under Egyptian domination and exploitation during this period, a position that also influenced the city’s international relations.</p><p>Methodologically the thesis examines areas of the earlier and the renewed excavations at Hazor, with the aim of discussing the city’s interregional relations and cultural belonging based on external influences in architectural structures (mainly temples), imported pottery and artistic expressions in small finds, supported by written evidence. Cultic influences are also considered.</p><p>Various origin and find contexts of the imported and culturally influenced material can be recognized, which imply three concepts in the field of interaction studies found within the framework of a modified World Systems Theory and also according to C. Renfrew’s Peer Polity Interaction model:</p><p>1) The northern influenced material at Hazor should be understood in the context of cultural identity. It continues from earlier periods and is maintained through external trade and the regional interaction between Canaanite city-states in the north, resulting in certain cultural homogeneity.</p><p>2) A core-periphery approach is used to explain the special unequal relation between Canaan and Egypt, in which Hazor might have possessed an integrating semi-peripheral role, a kind of diplomatic position between Egypt and its northern enemies. The city’s loyalty to Egypt is hinted at in documents and in the increasing evidences of emulation in elite contexts appearing on the site.</p><p>3) A model of ‘interregional interaction networks’ describes the organization of the trade which provided certain consumers at Hazor with the Aegean and Cypriote pottery and its desirable content. The cargo of the Ulu Burun and Cape Gelidonya ships and documents show that luxury items were transited from afar through Canaan. Such long-distance trade / exchange require professional traders that established networks along the main trade routes. The thesis suggests that Hazor possessed a node position in such a network.</p><p>Keywords: Hazor, Canaan, Eastern Mediterranean, Late Bronze Age, contacts, trade, temple architecture, Mycenaean pottery, Cypriote pottery, interregional interaction networks, emulation, peer polity interaction, centre-periphery approach.</p>
258

Near-Field Characterization of FM Transmitter Devices in Mobile Phone Applications

Khatun, MST Afroza January 2008 (has links)
<p>Mobile Phone, without this we can’t think to pass a day in presence. We have found a rapid increase of mobile phone users from a few years ago till now. Day by day the modern technologies allow the mobile phone to become smaller, cheaper, and more reliable. This also creates new possibilities for applications and integrations of the classical broadcast systems and modern mobile phone technologies. One example is the FM transmitter in mobile phone. The FM transmitter in a mobile phone is a “cool” feature which allows listening to the music content in phone on a car or home radio.</p><p> </p><p>This thesis work deals with the near field characterization of FM transmitters in mobile phone applications. The RF scientists and engineers neglect the near field zone because typical RF links operate at distances of many wavelengths away where near field effects are totally insignificant. But in this work we are interested in the near field properties of the FM transmitter. We measured the field intensity at near field and estimated the field strength at the far field region at 3 meters. To measure the field intensity and the effective radiated power we used HR1 near field scanner. As this is a new measurement approach, we made the validation of this system by measuring a reference dipole antenna at 880MHz and then compare the measured results to the CST simulation results. A basic phone model of FM transmitter has been created by CST simulation and a prototype has been made which was also used as our DUT. After validation of the near field measurement system we measured our DUTs (3 models-one cable fed prototype and two active devices) with the near field system and estimate the effective radiated power and field intensity at 3 meter. Furthermore, we measured our DUTs at 3 meter with a far field measurement system with optical fiber connection. A feasible relation between field strength and measured power was defined in order to correlate the near field scanner results with the far field measurement system.</p><p> </p><p>This paper also provides a short design guide line for built in FM antennas by relating the antenna size and placement to input power and the field strength in mobile phone FM transmitter application</p>
259

NIR-Sensitive Au-Au₂S Nanoparticles for Drug Delivery

Ren, L., Chow, Gan-Moog 01 1900 (has links)
Near IR (NIR) sensitive Au-Au₂S nanoparticles were prepared by mixing HAuCl₄ and Na₂S in aqueous solutions. An anti-tumor drug, cis-platin, was adsorbed onto Au-Au₂S nanoparticle surface via the 11-mercaptoundecanoic acid layers. The results showed that the degree of adsorption of cis-platin onto Au-Au₂S nanoparticles was controlled by the pH value of solution, and the drug release was sensitive to NIR irradiation. The cis-platin loaded Au-Au₂S nanoparticles can be potentially applied as NIR activated drug delivery carrier. / Singapore-MIT Alliance (SMA)
260

Advances in Seismic First-arrival Tomography

Gaines, David Paul 01 May 2011 (has links)
Seismic first-arrival tomography is a technique currently experiencing a renaissance in popularity due to the simplicity of implementation and promising results for delineating a variety of subsurface targets. The purpose of this study is to investigate seismic first-arrival tomography in a variety of settings and applications, and thus to provide a solid framework for future work. The study largely consists of two separate themes, hydrogeophysics and low-velocity anomaly detection. Hydrogeophysics is an emerging field whereby measured geophysical properties are used as proxies for physical properties of the subsurface. This study represents one of the first high-resolution hydrogeophysical investigations in the upper three meters of the subsurface using seismic first-arrival tomography, and consists of detecting shallow high-velocity zones that are interpreted to be perched water bodies on the basis of geophysical and hydrologic evidence. The delineation and imaging of the perched water bodies is further advanced using trend-analysis techniques. A second theme of this dissertation is the optimization of methods for delineating low-velocity anomalies at depth using seismic first-arrival tomography. In order to locate a low-velocity zone at Oak Ridge, Tennessee, multiple seismic lines were collected and correlated with site-wide geology. The integration of geologic and geophysical data-sets assisted in developing a comprehensive transport conceptual model, and provided a predictive framework for future geophysical investigations at Oak Ridge. As a second component of this theme, a systematic methodology for detecting and delineating shallow low-velocity zones is developed.

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